Solve for $x$ and $y$ using substitution. ${-6x-4y = 2}$ ${y = -3x+7}$
Explanation: Since $y$ has already been solved for, substitute $-3x+7$ for $y$ in the first equation. ${-6x - 4}{(-3x+7)}{= 2}$ Simplify and solve for $x$ $-6x+12x - 28 = 2$ $6x-28 = 2$ $6x-28{+28} = 2{+28}$ $6x = 30$ $\dfrac{6x}{{6}} = \dfrac{30}{{6}}$ ${x = 5}$ Now that you know ${x = 5}$ , plug it back into $\thinspace {y = -3x+7}\thinspace$ to find $y$ ${y = -3}{(5)}{ + 7}$ $y = -15 + 7$ $y = -8$ You can also plug ${x = 5}$ into $\thinspace {-6x-4y = 2}\thinspace$ and get the same answer for $y$ : ${-6}{(5)}{ - 4y = 2}$ ${y = -8}$